After the dam collapsed, authorities ordered the evacuation of nearly 200,000 residents in several northern California towns.

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Early 2017 temperatures ranked as the hottest in 122 years for the contiguous US.

A woman shields herself from the sun in Brooklyn Bridge Park, July 20, 2017 in the Brooklyn borough of New York City.
Getty Images

From April 2016 to March 2017, the US went through an unusually warm period that brought record-high temperatures to the Lower 48 states (everywhere but Alaska and Hawaii), according to the National Oceanic and Atmospheric Administration.

As The Washington Post noted, over that time period, the country's average temperature was 3.02 degrees Fahrenheit higher than the 20th-century average.

A groundbreaking study warned that continuing to burn fossil fuels at the current rate could bring atmospheric carbon dioxide to its highest concentration in 50 million years.

The gas-powered Valley Generating Station is seen in the San Fernando Valley on March 10, 2017 in Sun Valley, California.
Getty Images

According to the study published in April, if the world continues to emit greenhouse gases at its current pace, the global climate could reach a warming state in 2100 that scientists don't think the world has seen in the past 420 million years.

In April, one such study suggested that from 1990 to 2012, the rate of sea-level rise tripled from 1.1 millimeters to 3.1 millimeters per year. Another paper published in December predicted that the amount of rise would be double the highest estimates by 2100.

In June, Trump announced that the US will withdraw from the Paris agreement on climate change.

Donald Trump departs after announcing his decision that the US will withdraw from the landmark Paris climate agreement, in the Rose Garden of the White House, June 1, 2017.
Reuters

Trump's decision to pull the US out of the landmark Paris agreement would make the country the only one in the world not signed on to the accord.

The agreement, created in 2015, set a global goal to keep the planet from warming by more than 2 degrees Celsius above preindustrial levels. After that threshold, scientists say, the planet will see irreversible consequences including unpredictable superstorms, dramatic heat waves, increased wildfires, and severe drought.

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A Delaware-size iceberg broke off from Antarctica's Larsen C ice shelf in July.

Iceberg A-68 (center) drifts off the Antarctic Peninsula in this daytime satellite image, July 2017.LANCE/NASA

A giant crack in Antarctica's Larsen C caused a 1.1-trillion-ton iceberg— the third-largest in recorded history — to break off and float away.

Scientists say that the ice chunk, called A-68, will likely lie in the ocean for years until it ultimately melts into sea water.

A-68 won't noticeably raise sea levels, but the rest of the shelf is now less stable than it was before the rift. If its accompanying glacial ice collapses, sea levels could rise by up to four inches.

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A total solar eclipse captured America's attention in August.

The moon starts passing in front of the sun during a solar eclipse seen from Ross Lake, Northern Cascades National Park, Washington, U.S., August 21, 2017.
NASA

The Gulf of Mexico experienced a record-breaking hurricane season.

Marta Sostre Vazquez reacts as she starts to wade into the San Lorenzo Morovis river with her family, after Hurricane Maria, in Morovis, Puerto Rico, Wednesday, Sept. 27, 2017.
Gerald Herbert/AP

The 2017 Atlantic hurricane season was "extremely active," according to the definition used by the National Hurricane Center.

In August, Hurricane Harvey brought unprecedented rain levels to Houston area, and Irma plowed through the Virgin Islands, St. Martin, and other parts of the Caribbean before slamming into Florida. In September, Maria ripped roofs off homes and wiped out power in Dominica and Puerto Rico.

All three storms devastated communities, leaving thousands without housing and basic necessities like water and food.

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This summer and fall, monsoons left some cities in India, Nepal, Bangladesh, and Pakistan underwater.

It was the world's deadliest earthquake in 2017, and was felt as far away as Turkey and Pakistan.

The epicenter was near Ezgeleh, Iran (about 135 miles northeast of Baghdad) and hit the Iranian city of Pol-e Zahab particularly hard. Rubble destroyed buildings, cars, and other structures.

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In November, the Mount Agung volcano erupted in Bali, Indonesia.

A farmer is seen carrying grass while Mount Agung spews heavy volcanic ash on November 28, 2017 in Karangasem, Island of Bali, Indonesia.
Getty Images

On the Indonesian island of Bali, Mount Agung erupted four times over the course of two days in late November. The eruptions created plumes as high as 3.7 miles and sent ash 13,000 feet across the island.

As many as 100,000 locals in 22 villages were living in the expanded danger zone, Reuters reported. Flight cancellations also affected an estimated 59,000 passengers on 445 flights.

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In December, the Trump administration announced it will shrink the Bears Ears National Monument in Utah by 85%.

The 1.35 million-acre Bears Ears National Monument in southeastern Utah.
Bureau of Land Management

Decreasing the size of Bears Ears National Monument by 85% would make the move the largest reduction of a national monument in American history.

The Trump administration also announced plans to cut Utah's Grand Staircase-Escalante National Monument in half.

Environmentalists and some native nations say Trump's move will destroy artifacts of national heritage in these areas and threaten some 100,000 sites of archaeological importance. The decision will likely spur a lengthy legal battle.